Giving HFCs the cold shoulder: As U.S. appliance makers warm up to alternative blowing agents, Bayer studies performance of polyurethane foam blown with cyclopentane

Atlanta, September 24, 2012 — U.S. manufacturers of residential refrigerators currently use non-chlorine containing halocarbons (HFCs) as blowing agents for rigid polyurethane insulating foam. Recently, these HFCs have come under regulatory scrutiny due to their high global warming potential (GWP). Cyclopentane is already widely used by the appliance industry in many regions around the world due to its lower GWP. Now, some residential refrigerator manufacturers in the U.S. have also begun showing interest in this alternative blowing agent due to the uncertainty surrounding future use of HFCs.

Bayer MaterialScience LLC scientist Steve Aprahamian, Ph.D., studied the relationship between various processing variables and key physical properties of experimental polyurethane foam systems blown with cyclopentane. These experiments and their findings are detailed in a technical paper: "Effects of Processing Variables on a Polyurethane Foam System Blown with Cyclopentane." He will present his findings at 4 p.m., Monday, Sept. 24, as part of the Appliances/Energy Critical Foams session during the Center for the Polyurethanes Industry's 2012 Polyurethane Technical Conference in Atlanta.

Dr. Aprahamian chose two analogous polyurethane systems to study, including a typical cyclopentane-based system that would be used to manufacture rigid insulation for appliances, and an optimized system based on an increased catalyst level. During the experiment, he compared the two systems for string-gel time; minimum fill density; demold performance; core density; dimensional stability; thermal conductivity and compressive strength.

"Developing a polyurethane system involves many compromises," explained Dr. Aprahamian. "There is a balance of robustness of the system to allow large processing windows versus optimization of key performance indicators," he continued, emphasizing that in addition to that balance, it is important to be aware of not only key independent variables that can be directly controlled, but key dependent variables that can affect other dependent variables.

About Bayer MaterialScience LLC:

Bayer MaterialScience LLC is one of the leading producers of polymers and high-performance plastics in North America and is part of the global Bayer MaterialScience business with approximately 14,800 employees at 30 production sites around the world and 2011 sales of 10.8 billion euros. Bayer MaterialScience's 2011 sales in North America were $2.9 billion. The company manufactures high-tech polymer materials and develops innovative solutions for products used in many areas of daily life. The main segments served are the automotive, electrical and electronics, construction, medical, and sports and leisure industries. Sustainability is central to Bayer MaterialScience LLC's business and is based around the key areas of innovation, product stewardship, excellence in corporate management, social responsibility and respect for the environment.


Sean Kelly, Phone: 412-777-5200

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